Implement a click-to-view spoiler system

app/validators/status_length_validator.rb

@@ -0,0 +1,15 @@
+class StatusLengthValidator < ActiveModel::Validator
+  def validate(status)
+    if status.local? && !status.reblog?
+      combinedText = status.text
+      if (status.spoiler? && status.spoiler_text.present?)
+        combinedText = status.spoiler_text + "\n" + status.text
+      end
+
+      maxChars = 500
+      unless combinedText.length <= maxChars
+        status.errors[:text] << "is too long (maximum is #{maxChars})"
+      end
+    end
+  end
+end